Having air conditioning at home is a luxury that keeps people comfortable during the hottest months of the year, and it’s debated whether the AC should stay blasting or be turned off when people head to work during the day.
Some swear that turning off the AC when they’re gone for a few hours is the most energy-efficient, cost-saving method. Others say it’s better to leave it running continuously, preventing the system from straining to rapidly cool the house down after the home has gotten warmer throughout the day.
Three experts interviewed by The Associated Press agreed that setting the thermostat a few degrees higher than normal while you’re away is generally the best way to balance energy efficiency against comfort and humidity.
While turning an AC unit off for several hours and turning it back on can save money and energy compared to continuously running it, that approach can lead to mold problems in humid environments as well as wear and tear that can cause more frequent repairs. The equation can also vary depending on other factors including comfort level, AC unit type and building insulation.
According to the U.S. Department of Energy, adjusting your thermostat by 7-10 degrees Fahrenheit (4-6 degrees Celsius) for eight hours a day can save up to 10% a year on heating and cooling.
Experts say there are a lot of factors to consider when deciding what AC habits save the most energy and money.
“If you’re gone for like 15 minutes to go to the grocery store, you don’t get any gain" by turning off your AC, said Elizabeth Hewitt, professor and urban planning expert at Stony Brook University.
But as a general rule, “if you’re going for your work day, say for eight hours or so, you’ll almost always save more energy and money by turning things off," she said.
In some climates, however, turning off the AC might not be feasible, so residents can set back their AC a few degrees instead of blasting cold air all day.
In dry places like Arizona, you can let the home warm up more by raising the thermostat a few degrees higher. But in humid climates like Florida, air inside the home can become damp and harder to cool, and turning the AC off for long periods can increase the risk of mold since the system helps control indoor moisture.
Bumping up the thermostat by 1 degree Fahrenheit (0.6 degrees Celsius) yields about a 3% savings in cooling costs, said Patrick Phelan, mechanical engineering professor at Arizona State University.
Phelan also said leaving your AC off for hours and then turning it back on could lead to wear that results in more frequent repairs. That is because it can take AC systems 15 to 30 minutes after they are turned on to perform most efficiently.
How much energy and money you can save depends on the kind of home you live in, said Gregor Henze, an architectural engineering professor at the University of Colorado Boulder.
Homes built with heavy materials like concrete or brick hold in cool air longer, while older, draftier houses heat up faster. In less insulated homes, Henze said, it makes sense to adjust the thermostat even if you’re stepping out for just a few hours, because the indoor temperature can rise quickly.
Whether you have a window unit, a smart thermometer or central air could influence your savings.
Window units are generally less efficient because they’re installed in an open window, making it difficult to seal out hot air completely, said Hewitt. She added that spraying “cheap foam spray insulation in open windows or areas that are drafty is a really low-hanging fruit that doesn’t cost a lot of money and really helps retain the indoor temperature in your home.”
Phelan says smart thermostats are a handy tool to remove the mental burden of tinkering with your manual thermostat multiple times a day. Smart thermostats “learn” by monitoring the occupancy with a sensor and raise the temperature when no one is home to conserve energy and lower it when people return.
“If you’re going from just an ordinary manual thermostat to installing a smart one like a Nest, then you can expect something like 10% savings," said Phelan.
Each expert said simple steps like blocking sunlight can go a long way in keeping homes cool.
Henze pointed to “time-honored strategies” such as opening windows at night when it’s cooler. In dry climates, that night air doesn’t add much moisture, but in humid regions it can bring in dampness the AC will later need to remove.
Hewitt added that closing your blinds can make a difference of several degrees.
Phelan also noted that some blinds are designed to reflect sunlight and said tinted window films are another option.
O'Malley is a former Associated Press reporter.
The Associated Press’ climate and environmental coverage receives financial support from multiple private foundations. AP is solely responsible for all content. Find AP’s standards for working with philanthropies, a list of supporters and funded coverage areas at AP.org.
FILE - Sonel Telemaque, left, wipes sweat from his brow while installing a new air conditioning unit alongside Brian Hermosillo during record-breaking heat March 19, 2026, in Tempe, Ariz. (AP Photo/Caitlin O'Hara, File)
CATIA LA MAR, Venezuela (AP) — Rescuers pulled a 43-year-old security guard alive from a collapsed basement early Thursday, ending a grueling dayslong operation that became a symbol of hope after the devastation of twin earthquakes that struck Venezuela eight days earlier.
Hernán Alberto Gil Flores emerged to safety atop a stretcher surrounded by helmet-clad rescue workers after being trapped since June 24 under rubble in the basement of the Galerías Playa Grande shopping center in the coastal town in La Guaira.
Rescuers, who initially made contact with him over the weekend, worked for more than 100 hours to free him — navigating a highly unstable structure, torrential rain and persistent aftershocks to tunnel down to the survivor.
Teams carrying flags from around the world cheered as rescuers carried Gil Flores, wearing an oxygen mask and covered in an orange tarp, through throngs of people to an ambulance.
One Chilean rescuer carrying his stretcher pumped his fist in joy. A group of men in red Costa Rican Red Cross uniforms embraced and laughed in relief. Others broke out into applause.
“When we found him, he asked us not to tell his wife that he was alive, just in case he wouldn’t make it,” Costa Rican Red Cross rescuer Minyar Collado told The Associated Press, but she added “We were never going to leave him here.”
The rescue was considered a small miracle cutting through a week of tragedy. By supplying Gil Flores with food and water while they excavated the concrete, rescue teams were able to keep him alive far longer than the 48- to 72-hour threshold most operations give to find survivors in disasters.
Gil Flores, who worked as a night-shift security guard at the complex, was inside his small security cabin when the first violent tremor struck. While the surrounding concrete structure collapsed around him, his cabin held ground, shielding him from crushing debris and creating a vital pocket of air.
A specialized team from the Costa Rican Red Cross first detected signs of life and established contact with him Sunday.
His wife, Gusbimar González, told the AP that she grappled with despair for days before hearing that rescuers made contact.
“When I learned he was alive, I saw a ray of light in the darkness," she said. The couple has two children, ages 8 and 10.
The operation was coordinated by an urban search and rescue team of Chilean firefighters, who worked around the clock with specialized teams from the United States, Portugal, Mexico, Costa Rica, El Salvador and Venezuela.
Acting Venezuelan President Delcy Rodríguez celebrated the rescue on social media at a time that her government has come under fire for what many Venezuelans say has been an inadequate crisis response.
“We celebrate the greatness of humanity, when it is united for a single purpose: to save another. Thank you to our rescuers and to the support of the international rescuers,” she wrote on a post on X.
Teams used a telescopic camera to help maintain constant contact with Gil Flores, passing water and liquid nutrients through a narrow shaft to keep him hydrated during the final three days of the rescue.
María Paz Campos, a veteran firefighter from Chile, talked him through the entire operation and kept him calm during the final excruciating hours Thursday.
In a video published by Chilean firefighters in the hours before the rescue, Gil Flores is seen drawing, seemingly to pass the time. Campos then gently tells him to look at the camera and to wear protective goggles.
“I need you to keep the goggles on, for the small particles that are falling, to avoid them getting into your eye,” Campos told the Venezuelan survivor.
The collapse of the building was triggered by two back-to-back earthquakes on June 24 that registered magnitudes of 7.2 and 7.5, respectively. The shallow, violent tremors damaged or destroyed tens of thousands of buildings across northern Venezuela, killing more than 2,200 people, injuring over 11,000 and leaving La Guaira state as the hardest-hit region in the country.
Associated Press video journalists Andry Rincón and Brayan Antequero contributed to this report.
Rescue workers carry Hernán Alberto Gil Flores Gil after he was pulled from the rubble eight days after he was trapped by twin earthquakes that struck Catia La Mar, Venezuela, Thursday, July 2, 2026. (AP Photo/Fernando Vergara)
Rescue workers carry Hernán Alberto Gil Flores Gil after he was pulled from the rubble eight days after he was trapped by twin earthquakes that struck Catia La Mar, Venezuela, Thursday, July 2, 2026. (AP Photo/Fernando Vergara)
Chilean rescue workers carry Hernán Alberto Gil Flores after he was pulled from the rubble eight days after he was trapped by twin earthquakes that struck Catia La Mar, Venezuela, Thursday, July 2, 2026. (AP Photo/Fernando Vergara)
Rescue workers carry Alberto Gil after he was pulled from the rubble eight days after he was trapped by twin earthquakes that struck Catia La Mar, Venezuela. in Catia La Mar, Venezuela, Thursday, July 2, 2026. (AP Photo/Fernando Vergara)
Rescue workers carry Alberto Gil after he was pulled from the rubble eight days after he was trapped by twin earthquakes that struck Catia La Mar, Venezuela. in Catia La Mar, Venezuela, Thursday, July 2, 2026. (AP Photo/Fernando Vergara)
